Such spray nozzle assemblies serve for atomizing a medium, e.g. a perfume, varnish or other liquid. The medium requiring atomization is introduced into the nozzle channel of the spray nozzle assembly by means of a propellant or pumping mechanism here. Because of the peculiar geometry of the nozzle channel, the medium first undergoes condensation, flows through a small passage orifice, and escapes in the form of small droplets on the other side of the nozzle channel. The geometry of the nozzle channel is decisive for the spraying characteristics of the spray nozzle assembly here. Depending on use, very different properties regarding the droplets and their distribution in the spray jet may be desired, e.g. a flat spraying fan which concentrates the droplets in the fan centre or distributes them across the extent of the spraying fan in another, predetermined manner.
A spray nozzle assembly having the features of the preamble of claim 1 has been known from the U.S. Pat. No. 4,646,849, the entire contents of which is incorporated herein by reference. The known spray nozzle assembly is composed of a spraying nozzle and a holder. The two components are made of a metal and are brazed to each other. In particular, a very hard material which preferably is sintered tungsten carbide, is utilized for the spraying nozzle. The spraying nozzle is manufactured from a small cylindrical portion of this material by grinding a wedge-shaped groove into the pressure-end circle area of the cylinder and a trapezoidal groove, which extends perpendicularly to the wedge-shaped groove, into the opposed circle area of the cylinder. The two interengaging grooves form a passage orifice in the middle. The spraying nozzle is then inserted into a holder, which is also made of a metal, and is brazed thereto. The holder has formed therein a cylinder-shaped channel which leads to the wedge-shaped groove of the spraying nozzle. The known spraying nozzle, which is also called a cross-recessed nozzle, helps achieve beneficial spraying characteristics even though the known spray nozzle assembly is very expensive in manufacture.
Accordingly, it is the object of the invention to provide a spray nozzle assembly which has favourable spraying characteristics and can also be manufactured economically in large numbers.